Video-sharing websites such as YouTube and Vimeo have been the main driver for the increase. Most people post video of their families or events they’ve attended, rather than something staged or scripted, according to the survey.

Thirty-five percent who post video online, however, say they hope it will be seen by many people, or go viral. Only 5 percent say they regret a video they posted in the past.

Social networking sites and smartphones that can shoot video also contribute to the gains. Seventy-one percent of video posters upload to social networking sites. Forty percent use their cellphones to record video. And 23 percent rely on a mobile app to upload video to the Web. Several apps allow users to post video, including one made by San Diego-based Givit.

Of course, watching video online is still more common than posting. Seventy-eight percent of adults with Internet connections watch or download video. That’s up from 69 percent four years ago, according to the survey.